What is TA to maintain fields of Datasource?

This is quick tip on DataSource topic. From time to time we need to adjust settings of fields in datasource. Very common case (just to name one) is necessity to change some fields to be available for selection or set it as “Only Known in Exit”. 

In order to do so we go usually to TA RSO2 and we switch to Edit mode of datasource. However in this TA even we are in edit mode it is not possible to maintain above mentioned settings. Therefore there is another TA where we can do so. It is TA RSA6: